Abnormal metabolic brain imaging by MRS Abnormal brain choline/creatine ratio by MRS 2014-03-22T08:12:15Z UMLS:C4022760 A deviation from normal in the ratio of choline to creatine in the brain identified by magnetic resonance spectroscopy (MRS). HP:0012709 Creatine (Cr) is related to cell energy pathways, being both the substrate and product of creatine kinase. Creatine reflects the energy potential available in brain tissue. Its concentration in normal brain remains very high and stable due to high metabolic energy needs of brain cells. Its peak is noticed at 3.0 ppm. Creatine-Choline ratios are an important indicator of disease states such as demyelization.